The equation that represents the principle of the lever balance is:
- W₁ + W₂ = W3 + W4; option A.
<h3>What is the principle of moments?</h3>
The principle of moments states when a body is in equilibrium, the sum of the clockwise moment about a point equals the sum of anticlockwise moment about that point.
A see-saw represents a balanced system of moments.
The sum of clockwise moment = The sum of anticlockwise moments.
Assuming W1 and W2 are clockwise moments and W3 and W4 are anticlockwise moments.
The equation will b: W₁ + W₂ = W3 + W4
In conclusion, a balanced see-saw illustrates the principle of the lever balance.
Learn more about principle of moments at: brainly.com/question/20519177
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Answer:
(A) She needs to move the decimal point by 3 places
Answer:
t = 5.59x10⁴ y
Explanation:
To calculate the time for the ¹⁴C drops to 1.02 decays/h, we need to use the next equation:
(1)
<em>where 
: is the number of decays with time, A₀: is the initial activity, λ: is the decay constant and t: is the time.</em>
To find A₀ we can use the following equation:
(2)
<em>where N₀: is the initial number of particles of ¹⁴C in the 1.03g of the trees carbon </em>
From equation (2), the N₀ of the ¹⁴C in the trees carbon can be calculated as follows:
<em>where 
: is the tree's carbon mass, 
: is the Avogadro's number and 
: is the ¹²C mass. </em>
Similarly, from equation (2) λ is:
<em>where t 1/2: is the half-life of ¹⁴C= 5700 years </em>
So, the initial activity A₀ is:
Finally, we can calculate the time from equation (1):
I hope it helps you!
